A high-pressure-resistant and large-current power module to be mounted in a hybrid electric vehicle, an electric vehicle, etc. provides a large self-heating value or amount during operation of a semiconductor element. Accordingly, such a vehicle-mounted power module has to include a cooling structure having high heat dissipation performance.
As the power module including the cooling structure, for example, there is known a configuration that an insulating resin sheet, a metal layer serving as an electrode, and a semiconductor element are laminated on a cooler having coolant flow passages. The semiconductor element is fixed to the metal layer with solder, and the metal layer and the cooler are joined through the insulating resin sheet. This power module is configured to efficiently release the heat generated from the semiconductor element by the cooler through the metal layer which is superior in thermal conductivity and the thin-layer insulating resin sheet.
As a device to solder an electronic component onto an electronic circuit board, for example, Patent Document 1 discloses a reflow device for mounting an electronic component onto an electronic circuit board by heating, melting, and then cooling solder. Patent Document 1 describes that this reflow device is arranged so that a heat shielding member having a plurality of openings is interposed between a far-infrared heater and a subject to be processed to partially adjust a heating temperature in the surface of the electronic circuit board.